Vicky, Regina, Naoki, Sheila
We took squeeze data with PSAMs on ZM4 and ZM5 both at 120V, and four squeeze angles. Summary screenshot here, with these trends of squeezed BLRMS. All of the following data was done with frequency dependent squeezing.
- No Sqz (400 sec)
- Start: 1381106746
- Set ZM4 and ZM5 both to 120 V at 1381107446
- H1:AWC-ZM4_PSAMS_STRAIN_VOLTAGE 5.46593
- H1:AWC-ZM4_PSAMS_DEFOCUS_MON_MDIOPTER 258.34
- H1:AWC-ZM5_PSAMS_STRAIN_VOLTAGE 1.392
- H1:AWC-ZM5_PSAMS_DEFOCUS_MON_MDIOPTER -966.5
- We are leaving the injected squeeze angle at a demod phase of 150 degrees, although there looks to be some visible squeeze misrotation above the DARM pole
- Sqz (400 sec)
- Start: 1381107682
- Phase demod +150 degrees
- Anti sqz (400 sec)
- Start: 1381108725
- Phase demod +241.91 degrees
- +mid sqz (400 sec)
- Start: 1381109400
- Phase demod at +200 degrees
- -mid sqz (320 sec)
- Start: 1381110296
- Phase demod at +32 degrees
- Averaging ended early due to lockloss, almost definitely unrelated. We did not remeasure shot noise at the end or fully rotate into squeezing.
With ZM4/5 at 120/120 V, +/- mid squeeze have noticibly different misrotations across the band. In alog 71902 from Aug. 2 with PSAMS at 200/200V, we didn't see strong misrotations down to ~80 Hz. From FDS data on Aug 2, compare today's green/blue lines to the green and yellow +/- mid squeeze lines in this plot.
DTT saved at $(userapps)/sqz/h1/Templates/dtt/DARM/PSAMS_tests_Oct112023.xml
For reference, with ZM4/5 PSAMS at 200/200V (what we've been operating with in O4).
H1:AWC-ZM4_PSAMS_STRAIN_VOLTAGE 7.52377
H1:AWC-ZM4_PSAMS_DEFOCUS_MON_MDIOPTER 201.544
H1:AWC-ZM5_PSAMS_STRAIN_VOLTAGE 3.49813
H1:AWC-ZM5_PSAMS_DEFOCUS_MON_MDIOPTER -1030.69
I took more data with PSAMS ZM4/5 = 200V/200V, using the same injected sqz angles as above.
See comparisons of anti-squeezing and squeezing with PSAMS @ 200/200V (dotted lines) vs. 120/120V (solid lines).
- This dataset started about 35 min after NLN, so not totally thermalized yet.
- -mid sqz (600 sec)
- Start: 1381116279
- Phase demod at +32 degrees
- +mid sqz (600 sec)
- Start: 1381117087
- Phase demod at +200 degrees
- Anti sqz (600 sec)
- Start: 1381117845
- Phase demod +241.91 degrees
- No Sqz (600 sec)
- Start: 1381118732
- Sqz (600++ sec), back in observing
- Start: 1381120124
- Phase demod +150 degrees
Notes / thoughts:
- Unsqueezed DARM looks comparable before and now. Compare end of this dataset (black) with start of the last dataset (red). A bit quieter now below 40 Hz.
- Maybe more anti-squeezing at kHz (upper pink vs. black). Played with sqz angles, did not get more anti-sqz than the same +242deg angle.
- From SQZ-OMC mode scans with cold OM2 (e.g. Jan 2023, LHO:66946) and maximizing ADF-OMC transmission (e.g. July 2023, LHO:71270), I thought it suggests that 200/200V improves SQZ-OMC mode matching. Still leaves SQZ-IFO mode-matching unconstrained. I have not thought about anything relatd to mismatch phases. But if PSAMS 200/200 is minimizing a mismatch that introduces loss, that could be consistent with 200/200 giving more anti-squeezing at >kHz?
- SQZ might be flatter with 200/200V?
- FDS and both +/- Mid-SQZ all look more visually parallel compared to unsqueezed darm (red), and compared to each other (200/200 in dotted yellow vs. blue is more parallel than 120/120 in solid green vs. blue).
- FDS looks more parallel to unsqueezed darm too (lower purple vs. pink).
BLRMS trends here. All traces saved to same DTT file, $(userapps)/sqz/h1/Templates/dtt/DARM/PSAMS_tests_Oct112023.xml
Vicky, Sheila, Regina, Dorotea
We followed up by checking ZM Sliders to see if there is misalignment with different PSAMS was a factor in addition to the mode mismatches from changing PSAMS. There seems to be a large static alignment shift from changing PSAMS, we're not sure if it is fully compensated by ASC especially in yaw. We might do more measurements tomorrow to follow up.
| Squeezing | ZM4/ZM5 Voltage | Demod Phase (deg) | ZM4 P | ZM4 Y | ZM5 P | ZM5 Y | ZM6 P | ZM6 Y |
| +Mid SQZ | 120/120 | +200 | -41 | 255 | -176 | 339 | 780 | 805 |
| +Mid SQZ | 200/200 | +200 | -9.5 | 254 | -241 | 439 | 807* | 801* |
| -Mid SQZ | 120/120 | +32 | -12 | 257 | -176 | 351 | 753 | 793 |
| -Mid SQZ | 200/200 | +32 | -9.6 | 254 | -244 | 450 | 792 | 790 |
| ASQZ | 120/120 | +242 | -41 | 257 | -165 | 343 | 765 | 792 |
| ASQZ | 200/200 | +242 | -9.55 | 254 | -238 | 439 | 843 | 787 |
| FDS | 120/120 | +150 | -41 | 257 | -177 | 391 | 756 | 797 |
| FDS | 200/200 | +150 | -9.48 | 254 | -244 | 446 | 800 | 789 |
*+Mid SQZ: ZM6 was not flat for the 200/200 squeezing. It was increasing in P and Y for +Mid SQZ, didn't seem to reach the steady state. It seems like the ASC is keeping up better with 120/120 because the angles converged, whereas the angles of ZM5 and ZM6 for the 200/200 case kept increasing and did not reach steady state in the time given.
ASQZ: ZM5 pitch for 120/120 has some shaking, ZM6 pitch is rising and yaw is dropping
